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Lactating Holstein-Friesian cows kept in tie-stall barn were used as subjects in this study. Rectal examination, ultrasonography and blood sampling were conducted every other day and then daily after the day on which diameter of the corpus luteum decreased. After the luteal diameter decreased for 2 consecutive days, rectal and ultrasound examinations, blood sampling, and observation of estrous signs were conducted at 6-h intervals. Most of the estrous signs became obvious with the increase in estradiol-17β (E2) and became most remarkable 24 to 30 hours before ovulation, at which point the E2 peak and luteinizing hormone (LH) surge were achieved, and then weakened which progression to ovulation. The correlation between the intensity of four estrous signs (hyperemia and swelling of the intravaginal part of the uterus, opening of the external uterine orifice and viscosity of the cervical mucus) and the plasma E2 concentration was higher than that of three estrous signs (swelling of the vulva, contraction of the uterus, diameter of uterine horn) and the plasma E2 concentration. The relaxation of the intravaginal part of the uterus showed a unique change compared with the other estrous signs, and it became most obvious 6, 12 and 18 h before ovulation; this obviously relaxed period was consistent with the generally accepted theoretical optimal time for artificial insemination (AI), i.e., 6 to 24 h after initiation of estrus. These results suggest that observation of estrous signs by vaginoscopic examination gave useful information for detection of the optimal timing of AI in the periovulatory period in lactating dairy cows kept in a tie-stall barn.  相似文献   
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Salt plays an important role in the control of blood pressure in obesity and diabetes mellitus. In this study, we investigated physiological changes such as blood pressure and renal function in salt‐loaded female Spontaneously Diabetic Torii‐Leprfa (SDT fatty) rats. SDT fatty rats were given 1% NaCl in drinking water for 14 weeks, from 4 to 18 weeks of age. Significant salt‐sensitive hypertension was observed in the salt‐loaded SDT fatty rats. Moreover, the salt‐loaded rats showed a decrease of creatinine clearance and deterioration on pathological renal findings, including glomerulosclerosis and tubular and interstitial lesions. Female SDT fatty rat is a useful model for investigating the mechanisms of high salt sensitivity in obesity and diabetes mellitus.  相似文献   
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More accurate, rapid, and easy phenotyping tools are required to match the recent advances in high-throughput genotyping for accelerating breeding and genetic analysis. The conventional data recording in field notebooks and then inputting data to computers for further analysis is inefficient, time-consuming, laborious, and prone to human error. Here, we report WIPPER (for Wireless Plant Phenotyper), a new phenotyping platform that combines field phenotyping and data recording with the aid of Bluetooth communication, thus saving time and labor not only for field data recoding but also for inputting data to computers. Additionally, it eliminates the risk of human error associated with phenotyping and inputting data. We applied WIPPER to 100 individuals of a rice recombinant inbred line (RIL) for measuring leaf width and relative chlorophyll content (SPAD value), and were able to record an accurate data in a significantly reduced time compared with the conventional method of data collection. We are currently using WIPPER for routine management of rice germplasm including recording and documenting information on phenotypic data, seeds, and DNA for their accelerated utilization in crop breeding.  相似文献   
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Abstract: Background data during the gestation period were obtained from 128 Wistar Hannover GALAS rats and 26 Crl:CD(SD) pregnant rats in the control groups of our previous toxicity studies. The body weights of dams in the Wistar Hannover GALAS rats were significantly lower throughout the gestation period than those in the Crl:CD(SD) rats. In contrast, the time-dependent change in the body weight gain (%) of dams showed very similar trends in both strains. The mean number of live embryos/fetuses in the Wistar Hannover GALAS rats was 12.0, and was lower than that (14.5) in the Crl:CD(SD) rats. The placental weights gradually increased with pregnancy progression and reached a plateau on gestation day (GD) 19, although the embryo/fetal weights rapidly increased from GD 17 to GD 21. The embryo/fetal weights in the Wistar Hannover GALAS rats were significantly lower on only GD 21 than those in the Crl:CD(SD) rats. It is considered that this fetal weight difference between the strains develops during the fetal period, but not during the organogenesis period. In contrast, there were no differences in the placental weights between the two strains. Microscopically, the thickness of the labyrinth zone in the Wistar Hannover GALAS rats was thicker throughout the gestation period than that in the Crl:CD(SD) rats.  相似文献   
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In order to examine the toxicity profile of glycine, an authorized food additive, a solution of glycine in water for injection was administered orally (via gavage) to male SD rats (Crl:CD(SD)) once daily for 4 weeks at doses of 500, 1000 and 2000 mg/kg/day in a volume of 10 mL/kg. Control animals received vehicle only. No animals died, and no glycine-related changes were observed in body weight, food consumption, water consumption, hematology, organ weight, gross pathological examination or histopathological examination. In urinalysis, daily urinary volume and urinary Cl excretion were significantly higher in the 2000 mg/kg/day dose group, and urine pH and urinary protein showed lower trends in the glycine-treated groups. However, these changes were considered to be of little toxicological significance, because there were no histopathological changes in the kidneys or urinary bladder and no changes in other urinary parameters. As regards blood chemistry, phospholipids were significantly higher in the 2000 mg/kg/day dose group. However, the increase was small and was not considered to be toxicologically significant. In conclusion, none of the animals in any of the glycine-treated groups showed changes that were considered toxicologically significant. Therefore, the no-observed-adverse-effect level of glycine was estimated to be at least 2000 mg/kg/day under the conditions of this study.  相似文献   
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